Seminar
C*-methods for Topological Insulators , Dr. Danilo Polo Ojito, Yeshiva University (PostDoc), Fri, 28 March, 2025, 11:30 a.m. NCN II A-211
Abstract
Topological insulators are crystalline materials with an insulating in- terior and a conducting boundary due to the nontrivial topology of the bulk (deep within the material). In this talk, I will explain the underlying mechanism using -theory for C*-algebras. Specif- ically, we derive a groupoid c*-algebra that: 1. Encodes the dynamics of electrons in the infinite-size limit of a crystal. 2. Preserves the boundary conditions at the crystal's edges. 3. Supports a natural action by the point symmetries of the atomic lattice. As a result, I will show that specific derivations of the induced sequences in equivariant K-theory enumerate all non-trivial bulk- boundary correspondences. Post is here.